Increasing trend in intensity change of tropical cyclones before making landfall in China

This study investigates the climate trend in the intensity change (ΔV) of tropical cyclones (TCs) in the 24-h before making landfall in China during the period 1977–2022. Results reveal that the ΔV of TCs making landfall in Eastern China exhibits no discernible climate change, while a notable upward trend is observed in ΔV for TCs making landfall in Southern China (LTCSC). The upward trend in ΔV for LTCSC primarily results from the increasing proportion of intensifying TCs and the decreasing proportion of decaying TCs. This observed bimodal pattern in the intensity change proportions is further linked to the coastward trend of the locations of the lifetime maximum intensity (LMI) of LTCSC, along with significant poleward shift as well as westward migration. The westward shift of LMI locations may be mainly driven by the zonal changes in vertical wind shear, and the northward migration may be attributed to the combined effects of enhanced high-level divergence, elevated sea surface temperature, and reduced vertical wind shear as latitude increases.